So a few years ago I picked up the ATH-M50s before they got real popular and the price skyrocketed on them (I got them on a closeout sale for $89). When I got them I tested them to make sure they worked alright, then proceeded to break them in with white noise overnight for 3-4 nights before actually putting them on a testing them out. Loved em from the first time after that and they've only gotten better from there.
Today my ATH-M50s are well-used and have thousands of hours of listening on them. That being said I am looking for something to upgrade to from here. Something with a bigger sound stage and a broader range. I find my M50s lack in the low end and tend to be a bit "tinny" sometimes. I also need something closed-back as I use these in an office environment and I'd like to stick with circumaural cans as the on-ears tend to hurt after long periods of listening.
I listen to a wide range of music from various forms of Electronica (ambient, progressive, dubstep etc) to classic rock (Led Zeppelin, Stevie Ray Vaughn), and out to rockabilly and psychobilly and everything in between (like blues and classical). I really need something that is going to make any of these styles sound good as I go back and forth between them frequently throughout the day, so I don't want to have to be constantly fiddling with my settings to get them all to sound good.
My budget is pretty broad, but I'd like to not get into it any more than $500 including all gear (amps, cords etc) and the headphones themselves. My source is a new MacBook Pro 15" and I play most of my music through Spotify HD, which granted is not ideal, but then I don't expect the world either. I'd like to keep the gear on the smaller side since it has to take up desk space and I have to lock it up and take it back out every day.
Any insight you guys could give me on gear would be great. You guys are the ones that suggested the ATH-M50s to me and you definitely didn't lead me wrong. Hoping to get the same "sound" advice again (if you'll pardon the pun).